This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The collaborators would like to carry out mass spectrometric of cell signaling lipids. They are evaluating phosphatidyl inositol bis phosphate (PIP2) distributions in plasma membranes related to IgE receptor mediated signaling. They have already obtained some nice preliminary data and have published a paper with Prof. McLafferty, but this are of research is outside of his usual research, so he has referred the investigators to the BUSM Resource. The approach theywould like to use paralles that of some published work, but the difficulty of the work proposed here is greater. The primary result they seek is correlating their present biochemical data to certain peaks observed in the mass spectra. It also should be very interesting to quantify different PIP2 species. Some initial data has been obtained at BUSM and the student plans to visit to participate in further analyses.